regulator: add device tree support for max8997

Add device tree based discovery support for max8997.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Acked-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Reviewed-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/mfd/max8997.h b/include/linux/mfd/max8997.h
index 328d8e2..1d4a4fe 100644
--- a/include/linux/mfd/max8997.h
+++ b/include/linux/mfd/max8997.h
@@ -75,6 +75,7 @@
 struct max8997_regulator_data {
 	int id;
 	struct regulator_init_data *initdata;
+	struct device_node *reg_node;
 };
 
 enum max8997_muic_usb_type {